Are You A Biology Student? Take This Quiz As A Mock Test

Properly covering food helps to prevent the contamination of microorganisms from the air. When food is left uncovered, it is exposed to the surrounding environment, including the air which carries various microorganisms. These microorganisms can contaminate the food and lead to spoilage or foodborne illnesses. Therefore, covering food helps to maintain its safety and quality by preventing the entry of harmful microorganisms.

A pandemic is an outbreak of diseases that is wide spread. This means that it affects a large geographic area, such as multiple countries or continents, and affects a significant number of people. Unlike an outbreak or epidemic, which may be more localized, a pandemic has a global impact and can result in widespread illness and death.

Red blood cells contain a protein called hemoglobin, which binds to oxygen in the lungs and carries it to the body's cells. This process is crucial for the delivery of oxygen to tissues and organs throughout the body. Red blood cells do not engulf bacteria or aid in protein formation. They also do not regulate blood glucose levels. Therefore, the correct answer is C. Transport oxygen to the cells.

Sexually transmitted infections (STIs) are infections that are primarily spread through sexual activity. They can be caused by bacteria, viruses, or parasites. COVID-19 is a respiratory illness caused by the SARS-CoV-2 virus and is not classified as an STI. Staphylococcus is a type of bacteria that can cause various infections but is not specifically associated with STIs. AIDS (Acquired Immunodeficiency Syndrome) is a condition caused by the HIV virus, which can be transmitted sexually, among other ways. However, AIDS is a specific stage of HIV infection and not a general term for STIs. Therefore, the correct answer is D. STDs, which stands for sexually transmitted diseases.

Using a condom is the better way to avoid contacting sexually transmitted infections (STIs). Condoms act as a barrier method and can prevent the exchange of bodily fluids that can transmit STIs. They are highly effective in reducing the risk of contracting STIs, including HIV, gonorrhea, chlamydia, and syphilis. Other options mentioned in the question, such as getting pregnant, avoiding breastfeeding, and family planning, do not directly address the prevention of STIs.

Bacteria have proved very useful in medicine due to their ability to produce antibiotics. Antibiotics are substances that can kill or inhibit the growth of bacteria, making them essential in the treatment of bacterial infections. They work by targeting specific components or processes in bacterial cells, preventing their growth and replication. Antibiotics have revolutionized the field of medicine, allowing for the successful treatment of various bacterial diseases and saving countless lives.

The correct answer is C. Water lettuce n' tadpole n' fish. This is a food chain in the pond because water lettuce is a producer that provides food for tadpoles, which are primary consumers. The tadpoles, in turn, serve as food for fish, which are secondary consumers. This sequence represents the transfer of energy and nutrients from one organism to another in a pond ecosystem.

The correct answer is A. Mammalian skin. The skin plays a vital role in removing waste products from the body through sweat. Sweat is produced by sweat glands in the skin and contains waste products such as urea and salts. When we sweat, these waste products are excreted from the body, helping to maintain proper balance and eliminate toxins. The kidneys primarily filter waste from the blood, the liver detoxifies chemicals and metabolizes drugs, and the lungs are responsible for gas exchange. However, in this case, the function of removing waste products through sweat is specifically attributed to the mammalian skin.

The biosphere refers to all the places on Earth where life exists. It includes not only the surface of the Earth, but also the atmosphere and the oceans. The lithosphere refers to the solid outer layer of the Earth, the atmosphere refers to the layer of gases surrounding the Earth, and the hydrosphere refers to all the water on Earth. While these components are important for supporting life, they do not encompass all the places where life exists. Therefore, the correct answer is C. Biosphere.

Water loss is most rapid in sandy soil because sandy soil has larger particles with bigger gaps between them. These larger gaps allow water to easily drain through the soil, resulting in rapid water loss. In contrast, clayey soil has smaller particles with smaller gaps, which slows down the movement of water and reduces water loss. Sandy-loam and loamy soils have a mixture of sand, silt, and clay particles, which can retain water better than sandy soil and therefore have slower water loss.

The female anopheles mosquito is a vector of malaria fever because it is the only mosquito species mentioned that can transmit the malaria parasite to humans. Male mosquitoes do not transmit diseases, and the culex mosquito species mentioned is not known to be a vector for malaria. Therefore, the correct answer is A. Female anopheles mosquito.

Microorganisms play a crucial role in the production of fermented dairy products, bread, and alcoholic beverages. In the case of fermented dairy products, microorganisms such as bacteria and yeast are used to convert lactose into lactic acid, resulting in the formation of products like yogurt and cheese. Similarly, in the production of bread, yeast is responsible for the fermentation process, which produces carbon dioxide gas and causes the dough to rise. Finally, alcoholic beverages like beer and wine are produced through the fermentation of sugars by yeast, resulting in the formation of alcohol. Therefore, option D correctly identifies the products produced by microorganisms.

The cochlea is the part of the ear that enables hearing. It is a spiral-shaped, fluid-filled structure that contains tiny hair cells. When sound waves enter the ear, they cause the fluid in the cochlea to vibrate. These vibrations are then detected by the hair cells, which convert them into electrical signals that can be interpreted by the brain as sound. The cochlea plays a crucial role in the process of hearing and is responsible for our ability to perceive different pitches and tones.

A prokaryotic cell is characterized by the absence of a nucleus and other membrane-bound organelles. This means that the genetic material in a prokaryotic cell is not enclosed within a nucleus, but instead floats freely in the cytoplasm. Additionally, prokaryotic cells do not have any membrane-bound organelles such as mitochondria or endoplasmic reticulum. This lack of internal compartments distinguishes prokaryotic cells from eukaryotic cells, which have a nucleus and various membrane-bound organelles.

Animal nutrition involves the study of food substances and digestive enzymes. This includes understanding the different types of nutrients that animals need in their diet, such as carbohydrates, proteins, fats, vitamins, and minerals. It also involves studying how animals digest and absorb these nutrients, as well as the role of enzymes in breaking down food molecules. Understanding animal nutrition is important for ensuring that animals are provided with a balanced diet that meets their nutritional requirements for growth, reproduction, and overall health.

Muscles are attached to bones by means of tendons. Tendons are tough, fibrous connective tissues that connect muscles to bones. They are responsible for transmitting the force generated by the muscles to the bones, allowing movement and providing stability to the skeletal system. Ligaments, on the other hand, connect bones to other bones, cartilage is a flexible connective tissue found in various parts of the body, and nerves are responsible for transmitting signals between the brain and different parts of the body.

Mineral deposits are considered non-renewable resources because they take millions of years to form and cannot be replenished within a human lifetime. Once these minerals are extracted and used, they cannot be replaced. Forests, wildlife, and water, on the other hand, are renewable resources as they can be replenished through natural processes or human intervention.

Parasitism is a type of association where one organism benefits at the expense of another organism. In this relationship, the parasite feeds on or lives in the host organism, causing harm or even death. This disruption in the balance of nature occurs because parasites rely on the host for survival, often causing a decrease in the host population. As a result, the predator-prey relationships and overall ecosystem dynamics can be significantly altered, potentially leading to a destabilization of the balance of nature.

Cholera is caused by a bacterium, specifically Vibrio cholerae. This bacterium is transmitted through contaminated water and food, and it releases a toxin in the intestines that causes severe diarrhea and dehydration. Viruses, protozoans, and plasmodium do not cause cholera.

Freshwater habitats are characterized by low salt content, shallow water, and low density. High salinity, on the other hand, is a characteristic of saltwater habitats such as oceans and seas. Therefore, the correct answer is (b) high salinity.

Population characteristics refer to the various attributes or features of a population. These characteristics help in understanding the composition, distribution, and dynamics of a population. Population resizing, however, does not fall under the category of population characteristics. Instead, it refers to the process of changing the size of a population through various factors such as birth rates, death rates, immigration, and emigration. Therefore, population resizing is not considered as a population characteristic.

Synovial fluid is a thick, slippery fluid that lubricates the joints and reduces friction between the ends of bones in a movable joint. It also provides nutrients to the cartilage and helps in shock absorption. Serum, tissue, and blood plasma do not have the same lubricating properties as synovial fluid, making them less effective in easing friction between the bones.

Pathogens are defined as disease-causing microorganisms. These microorganisms can include bacteria, viruses, fungi, and parasites. They have the ability to invade and multiply within the host organism, leading to the development of various diseases. Pathogens can be transmitted through direct contact, airborne droplets, contaminated food or water, or vectors such as mosquitoes or ticks. Understanding pathogens and their mechanisms of infection is crucial in preventing and treating infectious diseases.

The correct answer is D. Dominant. In genetics, the term "dominant" refers to a trait or allele that is expressed or observed in an individual's phenotype, even if they only have one copy of the gene. In this context, the question is asking about a character that becomes apparent or visible when it is present alongside a contrasting character. This suggests that the character being referred to is dominant, as it is able to mask or override the expression of the contrasting character.

The term ecosystem refers to living organisms interacting with the physical environment. This includes the relationships and interactions between plants, animals, and their surroundings, such as the air, water, soil, and climate. Ecosystems are dynamic and complex systems where energy and nutrients flow through various organisms, and they are essential for maintaining the balance and sustainability of the natural world.

Ammonia is the correct answer because Amoeba excretes waste in the form of ammonia. Ammonia is a toxic compound that is produced as a result of protein metabolism in the organism. Amoeba does not have specialized excretory organs like kidneys, so it releases ammonia directly into its environment. Ammonia is a water-soluble compound that can easily diffuse out of the cell and into the surrounding water. This allows Amoeba to get rid of waste efficiently.

The products of respiration are carbon dioxide and water. During cellular respiration, glucose is broken down in the presence of oxygen to produce energy, carbon dioxide, and water. Carbon dioxide is a waste product that is released from the body through exhalation, while water is either excreted as urine or used by the body for various functions. Therefore, option D is the correct answer.

Bacteriophages are viruses that specifically infect bacteria. They attach to the surface of bacterial cells and inject their genetic material into them, taking over the bacterial machinery to produce more phages. This eventually leads to the lysis, or bursting, of the bacterial cell and the release of new phages. Bacteriophages are important in controlling bacterial populations and have been extensively studied for their potential use in phage therapy to treat bacterial infections.

During inspiration, the diaphragm contracts and moves downward, causing the thoracic cavity to increase in size. This allows for the entry of air into the lungs. Therefore, the statement "D. Diaphragm Relaxes" is incorrect because the diaphragm actually contracts during inspiration.

Rhizobium living in the root nodules of a leguminous plant is an example of mutualism. Mutualism is a type of symbiotic relationship where both organisms involved benefit from each other. In this case, Rhizobium provides nitrogen fixation to the plant, which helps the plant in obtaining essential nutrients. In return, the plant provides Rhizobium with a suitable environment and nutrients. Both organisms rely on each other for survival and benefit from this association.

Turbidity refers to the measure of the cloudiness or haziness of a fluid caused by suspended particles. It is a characteristic that is specific to aquatic habitats as it is influenced by factors such as sediment, algae, and other particles that are present in water bodies. Temperature, wind, and hydrogen ion concentration are ecological factors that can be found in both aquatic and terrestrial habitats.

A puddle is not considered a freshwater habitat because it is a small, temporary body of water that forms after rainfall or melting snow. Puddles are typically shallow and have a limited amount of water, which quickly evaporates or gets absorbed into the ground. They do not provide a stable environment for freshwater organisms to live and thrive. In contrast, ponds, swamps, and lakes are larger bodies of water that can support a variety of plant and animal species.

Blood platelets, also known as thrombocytes, are small cell fragments that play a crucial role in blood clotting. They do not have a nucleus, making them unique among blood cells. Platelets are formed in the red bone marrow along with other blood cells. However, their main function is to aid in clotting and prevent excessive bleeding, rather than neutralizing toxins in the blood.

Raw sewage disposal can lead to the growth of algal blooms in bodies of water. When raw sewage is released into water bodies, it introduces excess nutrients such as nitrogen and phosphorus. These nutrients act as fertilizers for algae, causing them to multiply rapidly. As the algae population increases, they consume large amounts of oxygen during photosynthesis. This depletes the oxygen content of the water, leading to hypoxic or anoxic conditions. This can be harmful to aquatic organisms that rely on oxygen, leading to fish kills and other negative impacts on the ecosystem.

The correct answer is D. Have intermediate hosts. Tsetse flies and mosquitoes do not have intermediate hosts. They directly transmit diseases to their hosts through their piercing and sucking mouthparts by injecting disease-causing organisms. They can harbor protozoa as disease agents and inject these organisms into the hosts, but they do not require intermediate hosts for disease transmission.

A colorimeter is an instrument that measures the absorbance or transmittance of light by a solution. In the context of determining the turbidity of water bodies, a colorimeter can be used to measure the amount of suspended particles or solids in the water. Turbidity refers to the cloudiness or haziness of water caused by these suspended particles. By measuring the absorbance or transmittance of light through the water sample, a colorimeter can provide a quantitative measurement of turbidity, helping to assess the water quality.

The functional roles of an organism refer to the specific position or role it occupies within its ecosystem. This includes its interactions with other organisms, its habitat preferences, and its role in nutrient cycling and energy flow. This concept is known as the organism's niche. The niche of an organism determines its place in the ecosystem and how it contributes to the overall functioning of the ecosystem.

Euglena is both holozoic and autotrophic. Holozoic organisms obtain their nutrition by ingesting solid food particles, while autotrophic organisms are able to produce their own food through photosynthesis. Euglena possesses chloroplasts, which allow it to carry out photosynthesis and produce its own food. Additionally, Euglena can also feed on other small organisms through phagocytosis, making it holozoic. Therefore, Euglena fits the criteria of being both holozoic and autotrophic.

Feeding is not a factor responsible for population sizes because while it may affect individual survival and reproductive success, it does not directly impact the overall size of a population. Factors such as nativity (birth rate), immigration (movement of individuals into a population), and mortality (death rate) have a more direct influence on population sizes as they affect the number of individuals entering, leaving, and being born or dying within a population.

A savanna is a biome characterized by a well-developed grass cover interspersed with scattered shrubs and small trees. This biome is typically found in tropical or subtropical regions with a pronounced dry season. The grasses in the savanna are adapted to fire and grazing, and the scattered trees and shrubs provide some shade and shelter. This type of biome is home to a diverse range of wildlife, including large herbivores like elephants and giraffes, as well as predators like lions and cheetahs.

The heredity material in a living cell is located inside the cytoplasm. The cytoplasm is a gel-like substance that fills the cell and contains various organelles, including the nucleus. The nucleus is where the heredity material, DNA, is stored. Therefore, the correct answer is B. Cytoplasm.

Animals living in benthic zones, which are the bottom regions of aquatic environments, often need to cling onto surfaces to avoid being swept away by currents. Possession of strong adhesives would be beneficial for these animals to attach themselves to rocks or other surfaces in order to stay in place. Therefore, possession of strong adhesives is a feature of animals living in benthic zones.

Nitrogen is not involved in the synthesis of chlorophyll. Chlorophyll is a green pigment found in plants and is responsible for photosynthesis, which is the process by which plants convert sunlight into energy. Nitrogen, on the other hand, is primarily needed for protein synthesis, activating certain enzymes, and promoting healthy vegetative growth in plants.

A chemo-autotroph is an organism that can produce its own food using energy obtained from chemical reactions. Bacteria are known to be chemo-autotrophs as they can convert inorganic substances into organic compounds through chemical reactions. Viruses are not considered living organisms as they cannot carry out metabolic processes on their own. Paramecium and Euglena are both eukaryotic organisms, but they are not chemo-autotrophs as they obtain their energy from other sources such as consuming organic matter or photosynthesis. Therefore, the correct answer is B. Bacteria.

Flocculation is the process of clumping together fine particles in a solution to form larger particles, which can then settle out more easily. In the case of acidic soil, flocculation can help improve it by binding together the small particles and increasing the soil's ability to retain water and nutrients. This can help neutralize the acidity and create a more balanced and fertile soil environment for plants to thrive.

Adaptation to avoid overcrowding includes various strategies such as dispersal of fruits and seeds and territorial behavior. Immigration, on the other hand, refers to the movement of individuals into a population from another area. This does not directly contribute to avoiding overcrowding, as it involves the addition of individuals to an already existing population. Therefore, immigration is not an adaptation to avoid overcrowding.

The correct answer is D. Meta population. A meta population refers to a group of spatially separated populations of the same species that interact with each other. In this scenario, the gradual replacement of one community by another in an orderly series suggests a pattern of movement and colonization by different populations. This aligns with the concept of a meta population, where populations disperse and establish in different areas over time.

Microorganisms that break down dead organisms and absorb their content are called decomposers. Consumers, on the other hand, are organisms that consume other organisms for energy and nutrients. Therefore, the correct answer should be A. Decomposer, not B. Consumers.

The most effective method of dealing with non-biodegradable pollutants is by burying them. This method ensures that the pollutants are safely contained and do not pose a threat to the environment or human health. Burying also prevents the pollutants from contaminating water sources or being released into the atmosphere. Recycling and incineration may be effective for certain types of pollutants, but burying is generally considered the best option for long-term containment and prevention of pollution. Dumping, on the other hand, is not a responsible or effective method as it simply involves disposing of the pollutants without any containment or proper management.

Hold fast for attachment is an adaptive feature in a marine habitat because it allows organisms to anchor themselves to the substrate and withstand the strong currents and waves in the marine environment. This adaptation helps them to avoid being swept away and provides stability and support for feeding, reproduction, and other activities.